The structure and dielectric properties of thin barium zirconate titanate films obtained by RF magnetron sputtering

Submicron thin layers of BaZr$_{x}$Ti$_{1-x}$O$_{3}$ are grown in-situ by RF magnetron sputtering of a ceramic target ($x$ = 0.50) on a substrate of Pt/$r$-cut leucosapphire Al$_2$O$_3$. It is shown that the composition of the ferroelectric layer is not identical to the composition of the sputtered target and is shifted toward barium zirconate. The reasons for such behavior are discussed. The obtained samples are characterized by high breakdown voltages (1 MV/cm and higher). The structural and high-frequency dielectric properties are studied, and high tunability of the capacitance of thin layers is revealed.